A novel monolithic fabrication method for a plastic microfluidic chip with liquid interconnecting ports

In the present study, a novel monolithic fabrication method was developed for the manufacturing of a plastic microfluidic chip with liquid interconnecting ports. As the present method can realize both interconnecting ports and through holes, which are essential components for the delivery of working fluids, in the plastic microfluidic chip, no additional processes and external ports are required. Furthermore, the connection of external silicone tubing can be simply achieved by utilizing an elastic deformation of the used tubing. As one representative example, a microinjection molding of a prototype microfluidic chip having two types of interconnecting ports was demonstrated. After obtaining upper and lower plates by the microinjection molding process utilizing mold cores with pin structures, the thermal bonding of the molded plates was carried out, resulting in the prototype plastic microfluidic chip with interconnecting ports. From microfluidic experiments using the fabricated prototype, it was found that the present method could be quite useful in various microfluidic applications.